Field of the Invention
The present invention relates to a system and a method for the computer-controlled measurement of workpieces. The system has at least one measuring machine and a device for entering parameters of the workpieces to be produced into a database.
In present-day mechanical engineering, it is essential for high-speed, efficient, low-cost and accurate production or processing of machine components. Such components are produced on numerically controlled machine tools, known as CNC processing machines. The CNC processing machines have a computer based controller, which controls the sequences of movements in the production of individual machine parts and workpieces. The computer based controller thereby issues control commands to electric motors of the processing machine, which uses its tools to process the workpiece to be produced in accordance with the control commands. The workpieces are in this case usually made of steel, but in principle other materials can also be processed in this way. The accuracy requirements for such workpieces can be tremendously high, for example in the production of printing machines it is necessary to measure the workpieces to within an accuracy of thousandths of a millimeter in order to ensure satisfactory running of the printing machine.
For this reason, it is necessary to measure the workpieces produced by a CNC processing machine after every processing operation, in order to ensure that the closest tolerances are maintained. Measuring the workpieces under these high accuracy requirements takes place by measuring machines on which the workpieces to be measured are fixed and are subsequently measured. If the measuring machine finds deviations from the setpoint values that go beyond the permissible tolerances, the workpiece must either be reprocessed or, if this is not possible, segregated out. For controlling the processing operation on a CNC processing machine and for carrying out the measuring operation on a measuring machine, the exact dimensions of the respective workpiece must be known to both devices. In other words, the dimensions of the workpiece must be stored in the control computers of the measuring machine and of the CNC processing machine, with the result that the workpiece can be processed and measured correspondingly.
In the case of present-day measuring machines, it is necessary for each measuring operation to enter the dimensions of the workpiece to be measured into the computer of the measuring machine in order to allow the workpiece to be checked subsequently for conformity with the data entered. Alternatively, a number of measuring operations are entered in advance in the computer of the measuring machine, but can only be changed on the machine. Since each manufacturer of measuring machines provides its own programming systems for its machine, reprogramming has to take place whenever the measuring machine is exchanged. Furthermore, each new measuring operation must be programmed on the associated measuring machine.